uTools-Manuals/docs/php/mysql_connect.html
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<title>打开一个到 MySQL 服务器的连接</title>
</head>
<body class="docs"><div id="layout">
<div id="layout-content"><div id="function.mysql-connect" class="refentry">
<div class="refnamediv">
<h1 class="refname">mysql_connect</h1>
<p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">mysql_connect</span> &mdash; <span class="dc-title">打开一个到 MySQL 服务器的连接</span></p>
</div>
<div id="function.mysql-connect-refsynopsisdiv">
<div class="warning"><strong class="warning">Warning</strong>
<p class="para">本扩展自 PHP 5.5.0
起已废弃,并在自 PHP 7.0.0 开始被移除。应使用 <a href="book.mysqli.html" class="link">MySQLi</a>
<a href="ref.pdo_mysql.html" class="link">PDO_MySQL</a> 扩展来替换之。参见
<a href="mysqlinfo.api.choosing.html" class="link">MySQL选择 API</a> 指南以及<a href="faq.databases.html#faq.databases.mysql.deprecated" class="link">相关 FAQ</a> 来获取更多信息。用以替代本函数的有:</p>
<ul class="simplelist">
<li class="member"><span class="function"><a href="mysqli_connect.html" class="function">mysqli_connect()</a></span></li>
<li class="member"><span class="methodname"><a href="pdo.construct.html" class="methodname">PDO::__construct()</a></span></li>
</ul>
</div>
</div>
<div class="refsect1 description" id="refsect1-function.mysql-connect-description">
<h3 class="title">说明</h3>
<div class="methodsynopsis dc-description">
<span class="methodname"><strong>mysql_connect</strong></span>
([ <span class="methodparam"><span class="type">string</span> <code class="parameter">$server</code></span>
[, <span class="methodparam"><span class="type">string</span> <code class="parameter">$username</code></span>
[, <span class="methodparam"><span class="type">string</span> <code class="parameter">$password</code></span>
[, <span class="methodparam"><span class="type">bool</span> <code class="parameter">$new_link</code></span>
[, <span class="methodparam"><span class="type">int</span> <code class="parameter">$client_flags</code></span>
]]]]] ) : <span class="type">resource</span></div>
<p class="para rdfs-comment">
打开或重复使用一个到 MySQL 服务器的连接。
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.mysql-connect-parameters">
<h3 class="title">参数</h3>
<p class="para">
<dl>
<dt>
<code class="parameter">server</code></dt>
<dd>
<p class="para">
MySQL 服务器。可以包括端口号,例如
&quot;hostname:port&quot;,或者到本地套接字的路径,例如对于 localhost 的 &quot;:/path/to/socket&quot;
</p>
<p class="para">
如果 PHP 指令 <a href="mysql.configuration.html#ini.mysql.default-host" class="link">
mysql.default_host</a> 未定义(默认情况),则默认值是 &#039;localhost:3306&#039;
<a href="ini.core.html#ini.sql.safe-mode" class="link">SQL 安全模式</a> 时,参数被忽略,总是使用 &#039;localhost:3306&#039;
</p>
</dd>
<dt>
<code class="parameter">username</code></dt>
<dd>
<p class="para">
用户名。默认值由 <a href="mysql.configuration.html#ini.mysql.default-user" class="link">mysql.default_user</a> 定义。
<a href="ini.core.html#ini.sql.safe-mode" class="link">SQL 安全模式</a> 时,参数被忽略,总是使用服务器进程所有者的用户名。
</p>
</dd>
<dt>
<code class="parameter">password</code></dt>
<dd>
<p class="para">
密码。默认值由<a href="mysql.configuration.html#ini.mysql.default-password" class="link">mysql.default_password</a>定义。在 <a href="ini.core.html#ini.sql.safe-mode" class="link">SQL 安全模式</a> 时,参数被忽略,总是使用空密码。
</p>
</dd>
<dt>
<code class="parameter">new_link</code></dt>
<dd>
<p class="para">
如果用同样的参数第二次调用
<span class="function"><strong>mysql_connect()</strong></span>,将不会建立新连接,而将返回已经打开的连接标识。参数
<code class="parameter">new_link</code> 改变此行为并使
<span class="function"><strong>mysql_connect()</strong></span> 总是打开新的连接,甚至当
<span class="function"><strong>mysql_connect()</strong></span> 曾在前面被用同样的参数调用过。
</p>
</dd>
<dt>
<code class="parameter">client_flags</code></dt>
<dd>
<p class="para">
<code class="parameter">client_flags</code>
参数可以是以下常量的组合:<strong><code>MYSQL_CLIENT_SSL</code></strong><strong><code>MYSQL_CLIENT_COMPRESS</code></strong><strong><code>MYSQL_CLIENT_IGNORE_SPACE</code></strong>
<strong><code>MYSQL_CLIENT_INTERACTIVE</code></strong>。进一步信息见<a href="mysql.constants.html#mysql.client-flags" class="xref">MySQL 客户端常量</a>
</p>
</dd>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.mysql-connect-returnvalues">
<h3 class="title">返回值</h3>
<p class="para">
如果成功则返回一个 MySQL 连接标识, 或者在失败时返回 <strong><code>FALSE</code></strong>
</p>
</div>
<div class="refsect1 changelog" id="refsect1-function.mysql-connect-changelog">
<h3 class="title">更新日志</h3>
<p class="para">
<table class="doctable informaltable">
<thead>
<tr>
<th>版本</th>
<th>说明</th>
</tr>
</thead>
<tbody class="tbody">
<tr>
<td>4.3.0</td>
<td>
添加 <code class="parameter">client_flags</code> 参数。
</td>
</tr>
<tr>
<td>4.2.0</td>
<td>
添加 <code class="parameter">new_link</code> 参数。
</td>
</tr>
<tr>
<td>3.0.10</td>
<td>
<code class="parameter">server</code> 添加 &quot;:/path/to/socket&quot; 支持。
</td>
</tr>
<tr>
<td>3.0.0</td>
<td>
<code class="parameter">server</code> 添加 &quot;:port&quot; 支持。
</td>
</tr>
</tbody>
</table>
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.mysql-connect-examples">
<h3 class="title">范例</h3>
<p class="para">
<div class="example" id="example-2120">
<p><strong>Example #1 <span class="function"><strong>mysql_connect()</strong></span> 例子</strong></p>
<div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$link&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">mysql_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">'localhost'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'mysql_user'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'mysql_password'</span><span style="color: #007700">);<br />if&nbsp;(!</span><span style="color: #0000BB">$link</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;die(</span><span style="color: #DD0000">'Could&nbsp;not&nbsp;connect:&nbsp;'&nbsp;</span><span style="color: #007700">.&nbsp;</span><span style="color: #0000BB">mysql_error</span><span style="color: #007700">());<br />}<br />echo&nbsp;</span><span style="color: #DD0000">'Connected&nbsp;successfully'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">mysql_close</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
</div>
</div>
</p>
<p class="para">
<div class="example" id="example-2121">
<p><strong>Example #2 <span class="function"><strong>mysql_connect()</strong></span> 例子:使用 <em>hostname:port</em> 语法</strong></p>
<div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /></span><span style="color: #FF8000">//&nbsp;we&nbsp;connect&nbsp;to&nbsp;example.com&nbsp;and&nbsp;port&nbsp;3307<br /></span><span style="color: #0000BB">$link&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">mysql_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">'example.com:3307'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'mysql_user'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'mysql_password'</span><span style="color: #007700">);<br />if&nbsp;(!</span><span style="color: #0000BB">$link</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;die(</span><span style="color: #DD0000">'Could&nbsp;not&nbsp;connect:&nbsp;'&nbsp;</span><span style="color: #007700">.&nbsp;</span><span style="color: #0000BB">mysql_error</span><span style="color: #007700">());<br />}<br />echo&nbsp;</span><span style="color: #DD0000">'Connected&nbsp;successfully'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">mysql_close</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">//&nbsp;we&nbsp;connect&nbsp;to&nbsp;localhost&nbsp;at&nbsp;port&nbsp;3307<br /></span><span style="color: #0000BB">$link&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">mysql_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">'127.0.0.1:3307'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'mysql_user'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'mysql_password'</span><span style="color: #007700">);<br />if&nbsp;(!</span><span style="color: #0000BB">$link</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;die(</span><span style="color: #DD0000">'Could&nbsp;not&nbsp;connect:&nbsp;'&nbsp;</span><span style="color: #007700">.&nbsp;</span><span style="color: #0000BB">mysql_error</span><span style="color: #007700">());<br />}<br />echo&nbsp;</span><span style="color: #DD0000">'Connected&nbsp;successfully'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">mysql_close</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
</div>
</div>
</p>
<p class="para">
<div class="example" id="example-2122">
<p><strong>Example #3 <span class="function"><strong>mysql_connect()</strong></span> 例子:使用 &quot;:/path/to/socket&quot; 语法</strong></p>
<div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /></span><span style="color: #FF8000">//&nbsp;we&nbsp;connect&nbsp;to&nbsp;localhost&nbsp;and&nbsp;socket&nbsp;e.g.&nbsp;/tmp/mysql.sock<br /><br />//variant&nbsp;1:&nbsp;ommit&nbsp;localhost<br /></span><span style="color: #0000BB">$link&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">mysql_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">'/tmp/mysql'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'mysql_user'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'mysql_password'</span><span style="color: #007700">);<br />if&nbsp;(!</span><span style="color: #0000BB">$link</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;die(</span><span style="color: #DD0000">'Could&nbsp;not&nbsp;connect:&nbsp;'&nbsp;</span><span style="color: #007700">.&nbsp;</span><span style="color: #0000BB">mysql_error</span><span style="color: #007700">());<br />}<br />echo&nbsp;</span><span style="color: #DD0000">'Connected&nbsp;successfully'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">mysql_close</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">);<br /><br /><br /></span><span style="color: #FF8000">//&nbsp;variant&nbsp;2:&nbsp;with&nbsp;localhost<br /></span><span style="color: #0000BB">$link&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">mysql_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">'localhost:/tmp/mysql.sock'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'mysql_user'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'mysql_password'</span><span style="color: #007700">);<br />if&nbsp;(!</span><span style="color: #0000BB">$link</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;die(</span><span style="color: #DD0000">'Could&nbsp;not&nbsp;connect:&nbsp;'&nbsp;</span><span style="color: #007700">.&nbsp;</span><span style="color: #0000BB">mysql_error</span><span style="color: #007700">());<br />}<br />echo&nbsp;</span><span style="color: #DD0000">'Connected&nbsp;successfully'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">mysql_close</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
</div>
</div>
</p>
</div>
<div class="refsect1 notes" id="refsect1-function.mysql-connect-notes">
<h3 class="title">注释</h3>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">本扩展自 PHP 5.5.0
起已废弃,并在自 PHP 7.0.0 开始被移除。应使用 <a href="book.mysqli.html" class="link">MySQLi</a>
<a href="ref.pdo_mysql.html" class="link">PDO_MySQL</a> 扩展来替换之。参见
<a href="mysqlinfo.api.choosing.html" class="link">MySQL选择 API</a> 指南以及<a href="faq.databases.html#faq.databases.mysql.deprecated" class="link">相关 FAQ</a> 来获取更多信息。用以替代本函数的有:</p>
<p class="para">
<ul class="simplelist">
<li class="member"><span class="function"><a href="mysqli_connect.html" class="function">mysqli_connect()</a></span></li>
<li class="member"><span class="methodname"><a href="pdo.construct.html" class="methodname">PDO::__construct()</a></span></li>
</ul>
</p>
</p></blockquote>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
只要将 server 指定为 &quot;localhost&quot;
&quot;localhost:port&quot;MySQL 客户端库会越过此值并尝试连接到本地套接字Windows
中的名字管道)。如果想用 TCP/IP应该用 &quot;127.0.0.1&quot;
代替 &quot;localhost&quot;。如果 MySQL 客户端库试图连接到一个错误的本地套接字,则应该在
PHP 配置中设定 <a href="mysql.configuration.html#ini.mysql.default-host" class="xref"></a>
的正确路径并把 server 留空。
</p>
</p></blockquote>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
脚本一结束,到服务器的连接就被关闭,除非之前已经明确调用
<span class="function"><a href="mysql_close.html" class="function">mysql_close()</a></span> 关闭了。
</p>
</p></blockquote>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
可以在函数名前加上一个
<a href="language.operators.errorcontrol.html" class="link">@</a>
来抑制出错时的错误信息。
</p>
</p></blockquote>
</div>
<div class="refsect1 seealso" id="refsect1-function.mysql-connect-seealso">
<h3 class="title">参见</h3>
<p class="para">
<ul class="simplelist">
<li class="member"><span class="function"><a href="mysql_pconnect.html" class="function" rel="rdfs-seeAlso">mysql_pconnect()</a> - 打开一个到 MySQL 服务器的持久连接</span></li>
<li class="member"><span class="function"><a href="mysql_close.html" class="function" rel="rdfs-seeAlso">mysql_close()</a> - 关闭 MySQL 连接</span></li>
</ul>
</p>
</div>
</div></div></div></body></html>